That is a wide region of sluggish fen where the stream becomes tortuous and much divided. There the Entwash flows in by many mouths from the Forest of Fangorn in the west.
”
–Celeborn in The Fellowship of the Ring, Farewell to Lórien
The Mouths of Entwash is a biome located around where the river Entwash splits into several smaller streams and meets the Anduin. It is a marsh biome, similar to Swanfleet, and is mostly uninhabited. These swamps were created due to the floods resulting from the "Long Winter".
The swamps of Nindalf, opposite this biome on the other side of the Anduin, is the overflow from the mouths of the Entwash.
This biome like other swampland biome mainly consists of many pools of water and occasional patches of quagmire. Stunted trees and rotten logs also often spawn here.
Upon entering the biome the player earns the achievement "Last Marsh of the Ents'".
Uplands: A version of the marshes with fewer pools, higher land generation, and many more trees.
Lowlands: A variant of the marshes that is more or less flat, and is more like a vast pool choked with bits of land and quagmire.
There is no standard version of the Mouths of Entwash or any swamp biome.
Mobs[]
There are no NPCs that spawn here, not even Orcs at night, but normal Minecraft mobs (farm animals and horses) do.
Mining[]
The Mouths of Entwash feature the standard ore distribution, but unlike other biomes they also feature Gondor Rock below the surface. This rock is essential for the crafting of Gondorian building materials, and can be found in a thin layer beneath the dirt surface of the biome, in patches underground, and in boulders on the surface.
Vegetation[]
This biome mainly contains tall grasses and fern plants along with occasional other plants such as flowers or sugarcane. Some trees also spawn here alongside the rotten remains of other trees. Willows are common here.